Condenser and transformer unit



L. M. PERKINS CONDENSER AND TRANSFORMER UNIT June 3, 1930.

Filed Nov. 27, 1928 may Patented June 3, 1930 UNITED STATES PATENT OFFICE LAURENCE MERTON PERKINS, OF ANDERSON, INDIANA, ASSIGNOR TO DELCO-REMY CORPORATION, OF DAYTON, OHIO, A CORPORATION OF DELAWARE CONDENSER AND TRANSFORMER UNIT Application filed November 27, 1928. Serial No. 322,276.

a split phase motor.

Upon the same leg of the core of the autotransformer that the coil is mounted is a pair of insulated sheet members each having a concave end, which fits the cylindrical surface of one of the spiral condensers whereby s? the condenser and the autotransformer are rigidly held in position and in alignment. Surrounding the autotransformer and the condensers is a housing which is water and dust proof.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings, wherein a preferred embodiment of one form of the present invention is clearly shown.

In the drawings:

Fig. 1 is a plan view of the assembly with the cover removed.

Fig. 2 is a side view of the assembly with the side removed.

Fig. 3 is a partial end view showing the terminals of the transformer.

Fig. 4 is a schematic diagram of the circuit.

Referring to the drawings, the reference character indicates the bottom of the metallic support or casing which is turned upwardly around the entire periphery, as inclicated by the reference character 11. 12 is a metallic side made from a continuous strip bent at the corners 13--1313 overlapping at the corner 14. After being shaped, the side is inserted within the upturned edge 11 of the metallic bottom. The bottom 10 and the sides 12 are lined on the interior with sheets of insulating material 15 and 16 respectively, the strip 16 extending continuously around the four sides bein overlapped at 17. The upper edge of 16 is bent away, as shown by reference character 18, in order to provide space for the terminal assembly 50. Near the top of the insulating member 16 there are provided three apertures 19 permitting the terminals 1, 2 and 3 to pass through the insulation. The casing is supported on supports 24L secured to the casing by means of screws 25.

The transformer 26 is an autotransformer with three taps 27, 28 and 29. The reactance unit as applied to one phase of a split phase motor has been disclosed in my copending application Serial No. 322,275, filed November 27, 1928. The transformer 26 has the rectangular core 30 having one leg 3O upon which is mounted the winding 31, insulated from the core by insulating members 32 and 33. Members 32 and 33 each have a concave portion 34 which is curved so as to have the same contour as does the periphery of the cylindrical shaped condenser 35. Condensers 35 and 36 are each made from a pair of sheets of condenser foil insulated from each other by sheets of insulating material, sheets of condenser foil and the sheets of insulating material being wound on a tubular core 39, the sheets of condenser foil forming spiral condenser plates. A plane determined by the centers of the tubular cores 39 coincide with a plane passing through the center of each leg of the core. The taps 27 and 29 are connected to the spirally arranged condensers 35 and 36 by means of leads 37 and 38. The lead 37 being soldered to the edges of the positive spiral plates of each of the condensers, and the lead 38 being soldered to the corresponding negative spiral plates, thereby connecting the condensers in parallel with the winding of the autotransformer. The tap 28 is connected to the winding at some predetermined point 40 as best seen in Fig. 4. The posts or taps 27, 28 and 29 are connected to the leads 1, 2 and 3 respectively. When using this arrangement of an autotransformer and condensers in one phase of a split phase motor, the capacitance in one phase may be changed by changing the taps on the autotransformer from say 1-2, to 1-3.

After the transformer 26 and the condensers 35 and 36 are assembled, a metallic cover 21 is fitted over the top of the casing. Within this casing aremounted two partitions l3 and 44 made from an insulating material and inserted between the condenser units 35 and 36, and between the condenser 35 and transformer 26, thereby electrically separating these units. Suitable apertures have been provided for the various conductors passing through these partitions. The condensers 35 and 36 and transformer 26 rest on the insulation 15.

After the condensers, transformer and the partitions have been inserted into the casing, but before the cover 21 has been placed in position, the voids l5 are filled with a suitable insulating material which may be poured into these voids while hot and solidifying upon being cooled. to rigidly hold the parts in assembled position so that any vibration of the casing will not affect the assembly. Black wax has been found to be a suitable insulating material for this purpose. All the edges 22 are soldered so as to exclude all dust and moisture.

In an aperture 42 near the top and in one end of the casing is inserted the terminal assembly 50, consisting of a sleeve having a shoulder 52, which cooperates with a nut 51, screw-threaded on the sleeve 53, on the inside of the casing to hold it in place. In the center of the sleeve 53 is a suitable core 5% having three apertures, one for each of the leads 1, 2 and 3. The groove 55 permits the tightening of bolt 56 in the sleeve 53, in order that the core 5% may be held in place, as clearly shown in Figs. 1 and 3.

, This reactance unit has been assembled in the minimum amount of space, each part be ing rigidly held in position by the insulating material within the casing and the casing per se. The insulating material is a protection against short circuits and the metallic casing is a protection again dampness, moisture and dust and also serves the purpose of electrically screening the parts within the apparatus from all electrostatic and electromagnetic disturbances outside of the casing.

vVliile the form of embodiment of the present invention as herein disclosed, constitutes a preferred form, it is to be understood that other forms might be adopted, all coming within the scope of the claims which follow.

lVhat is claimed is as follows:

1. In a reaetance unit comprising, the combination of a plurality of spiral condensers, each having a tubular core and a cylindrical surface, with an autotransformer consisting of a rectangular magnetic core, said core having a pair of vertical legs, a coil mounted upon one of said legs, said. coil having a plurality of taps, apair of insulating sheets, each having a concave end, linking said leg for insulating the coil from said magnetic core, the eoncave end of each of said insulating sheets cooperating with the cylindrical surface of one said condensers to hold the axis of the tubular core of the condenser in the plane determined by the vertical axes passing through the center of each of the legs.

2. in a reaetance unit comprising, the combination of a plurality of spiral condensers, each having a cylindrical surface and a tubular core, with an autotransformer consisting of a rectangular core having a rectangular window, the sides of the window being parallel to the sides of the core thereby forming a pair of vertical. legs, a coil linking one of said legs, a pair of insulating members linking the leg for insulating the coi from the core, each insulating member having a concave end so as to lit the cylindrical surface of one of the condensers to hold the condenser, thereby maintaining the axes of the condensers in a plane coinciding with the plane determined by the vertical axes passing through the centers of each of the legs.

3. A reactance unit comprising, in combination a plurality of condensers, each includ' ing a core, positive and negative plates spirally wound on said core insulating material intermediate the plates, all the cores being parallel and being in a common plane, an autotransformer consisting of a rectangular magnetic core having a rectangular window therein, a coil with a plurality of taps mounted on one leg of said core, a pair of insulating members linking said leg, each of said insulating members having the end remote from th core concave shaped, the concave ends operating with the cylindrical surface of one of the condensers to hold the condenser and the magnetic core of the transformer in a plane coinciding with said common plane, a casing for said reactance unit having each of the condensers and the core of the autotransformer resting on the base of the casing.

In a reactance unit comprising the combination of a plurality of spiral condensers, each having a tubular core, with an autotransformer, consisting of a core having a window and a coil linking said core, the axis of said coil and the axis of eachv of the condenser cores lying in a common plane.

In testimony whereof I hereto affix my signatur V LAURENCE MERTON PERKINS. 

